An integral part of an aircraft fuselage is the cargo door assembly through which cargo is loaded to and unloaded from the aircraft. The door assemblies of modern commercial aircraft include latch mechanisms that lock the door in place when it is closed and unlock the door when it is opened. The actual opening and closing of the door assemblies are controlled by handle assemblies that actuate the latch mechanisms. Most of the handle assemblies are provided with interior and exterior handles so that the door assemblies in which they are installed may be opened or closed from either inside or outside the aircraft.
An aircraft door handle assembly is typically designed to perform a number of different functions and to operate properly regardless of the harshness of the environmental conditions to which it may be exposed. Most handle assemblies are constructed so that either the interior or exterior handle can be used to actuate the latching mechanism regardless of which handle was last used to actuate the mechanism. This is primarily a safety feature to allow a cargo handler to open the door from the inside of the cargo hold in case the door was closed while the handler was still inside the cargo hold.
The typical handle assembly includes an exterior, or outside handle that is normally stored flush with the outer skin of the aircraft so as to not degrade the aerodynamic efficiency of the fuselage. The handle assembly must keep the outside handle locked in place so that it does not “pop out” in flight regardless of the large pressure differentials that may develop between the inside of the aircraft, which is pressurized, and the outside low ambient pressure at high altitudes. Inadvertent extension of the outside handle can disrupt the airflow around the aircraft and degrade aerodynamic performance. Moreover, extension of the outside handle could lead to its movement so as to cause self-actuation of the handle assembly and the associated latch mechanism. With an unpressurized cabin this could result in the door inadvertently opening while the aircraft is in flight. Moreover, a handle assembly must also be designed to operate even though its exterior components may be exposed to significant amounts of rain or snow.
Aircraft door handle assemblies have been provided that meet one or more of these design criteria. Some aircraft door handle assemblies are constructed so that they are integrally connected to the doors in which they are employed. In the event the handle assembly requires extensive maintenance, the assembly cannot be simply replaced; the whole aircraft must be taken out of service.
In light of the shortcomings in the prior art, there exists a need for an improved door handle assembly for controlling the opening and closing of an aircraft door.